This type of regulator is a typical reverse magnetron structure, which is not afraid of air exposure due to the absence of hot filament. It adopts ultra-high vacuum detachable sealed electrode structure, which is easy to clean and maintain, and has reliable sealing performance. With auxiliary excitation device, start quickly to measure stability. Precise symmetrical orthogonal electromagnetic field configuration ensures high measurement accuracy and good repeatability. Especially suitable for high vacuum and ultra high vacuum measurement.
Main technical parameters
1. Measurement range: 1×10-1~1×10-7Pa
2. Working voltage: 3/3.3kV
3. Working current: 0.7mA
4. Cathode material: non-magnetic stainless steel
5. Insulator material: 95 ceramics
6. Core seal material: pure silver or fluororubber seal ring
7. Vacuum connection form and baking temperature:
CF35 ultra-high flange 450℃
KF40 quick discharge flange 120℃
KF25 quick discharge flange 120℃
KF16 quick discharge flange 120℃
Φ 15.5 + / – 0.1 metal 120 ℃
Cold cathode ionization gauge and hot cathode ionization gauge, is to use the low voltage state down electric current and the relationship between the gas pressure of vacuum measurement. Cold cathode ionization gauge tube structure for the diode. In a glass tube encapsulation of two parallel metal plate as cathode, cathode materials – as with high secondary emission coefficient under ion bombardment of nickel, pliers and stainless steel, etc. Between level Yin furnish a ring anode, anode material for nickel, phase, stainless steel and gold brocade chromium. Cold emission (field emission by cosmic rays, the photoelectric effect or gas ionization, etc.) produced by a small amount of the initial electron, accelerated under electric fields, When it has a certain energy, can make gas ionization. Ionization produced by the positive ion in strong electric field, under the action of high-speed bombarding cathode, cathode and hit the secondary electric at the table, the electrons in the positive anode, and collisions with gas molecules, and the gas ionization, such a process is ongoing, finally stays in the regulation of electrode is formed between the discharge. At the same time, in the field with a heart in orthogonal magnetic field, the charged particles in a magnetic field along a spiral path forward movement, extended the charged particles flying distance, improve the collision probability. Such a small amount of the initial electronic, in under the action of electric and magnetic field, A large number of electrons and ions are produced in a short time. As long as the relationship between discharge current and gas pressure is known, the vacuum degree can be measured.
In actual work, the discharge current and is not a simple linear relationship between the pressure, so the price must be approved by the school of the standard pressure value of the corresponding relationship between discharge current calibration curve, according to the calibration curve, use of cathode ionization gauge discharge current instructions, before vacuum measurement. Through 8 a 14 R in the limit of flow resistance, and its main role in protection regulations. Today the discharge current increasing, the regulation between the electrode voltage drops, secured by regulation of current increases to produce arc trust of malicious programs. But we should pay attention to, as a result of the existence of R, lower the gauge tube voltage between electrodes, Will cause sensitive skin to drop.
It can be seen from the above measurement principles that the cold-cathode ionization vacuum juice measurement circuit does not need stable monitoring of the emission current, nor does it need an ion current amplifier (because the discharge current is very large, it can be measured directly with a microammeter), and is much simpler than that of the hot-cathode ionization vacuum juice measurement circuit.
The cold cathode ionization gramme consists of dc high voltage power supply and discharge current measuring instrument.
The measurement range of cold cathode ionization gauge is generally 1-10^-5 pA.